In conventional positional information delivery technologies, there are the latitude/longitude are a globally representing method. However, latitude/longitude are suited to represent a position on a sphere, but are not suited as a coordinate system for measuring a distance and an area because of its lack of user-friendliness due to a sexagesimal number system. Thus, planar orthogonal coordinates (X, Y coordinates) are required for measurements and the like, in which a spherical surface is regarded to be a pseudo-flat surface. Internationally, a UTM (Universal traversal Mercator) coordinate system has been used, where the globe is divided into 60 zones along the longitudes, and the origin is placed at the intersection of a central longitude of each zone with the equator.
Since Japan extends over five zones, there are five coordinate origins. However, since Japan is located far from the origins on the equator, large distortions and a large number of digits create disadvantages. For this reason, Japan has employed a 19-coordinate system as a public coordinate system for measurements in a form in which one origin is shared by groups of prefectures. This coordinate system, as will be understood from the name, has 19 coordinate origins for all of Japan (hereinafter, the 19-coordinate system and UTM coordinate system are collectively called as the “X, Y coordinates”).
The planar orthogonal coordinate system has disadvantages of requiring a large number of origins and reference points for making corrections and of being usable only for local applications within the respective origins. In other words, overall Japan cannot be represented as one system. For this reason, the planar orthogonal coordinate system can be utilized only in limited applications such as public measurements, but cannot be utilized in many applications which are deeply related to daily life such as traffic and distribution.
The latitude/longitude, and coordinate values of the X, Y coordinates are used when a position itself is represented and when a distance or an area is measured, but any of these coordinate systems presents point information only indicative of that point. However, for use in statistic processing, for example, demographic distribution, a coordinate system must have an area rather than a point. In other words, a mesh structure is required.
As global mesh codes, there are a Marsden square code, a GEBCO (General Bathymetric Chart of the Oceans) mesh code, and the like. Any of these code systems divides the latitude/longitude every ten degrees, and numbers the resulting segments, but the numbering lacks regularity. In addition, they also involve a quadrisection in a sub-division process and therefore lack continuity, thus making themselves difficult to use. Also, Oracle Co. employs a unique mesh code which supports the world, but involves repetitions of quadrisections. Though regarded as efficient from a mathematical point of view, it is difficult for a person who views it to understand this mesh code system.
In Japan, there is also a mesh code system which is defined by JIS (Japanese Industrial Standards), called “regional mesh code.”
Though created on the basis of the latitude/longitude, this code also has the disadvantage that there is a lack of continuity in the numbers because a primary mesh is vertically and horizontally divided equally into eight to create a secondary mesh. Also, the meshes are uniformly sectioned by one degree of longitude in the east-west direction, and by 40 minutes of latitude in the south-north direction to define squares, but this can be applied only to a north-east region, and the shape of meshes becomes oblong in Kagoshima which is located in the southern region of Japan, thus presenting the disadvantage that the vertical and horizontal unit lengths are different.
Further, since there are deviations between Japan's Japan positioning system and the global positioning system in the latitude/longitude which are used to represent positions, it has been pointed out previously that the deviations cause problems in applications such as aircraft. Also, while GPS's have been available on the market for use in leisure ocean activities and the like, they display longitude and latitude according to WGS84 which are the basis of the system used in the United States, and have the problem that there is a deviation of 400-500 meters from the longitude and latitude on commercially available maps in the Japan positioning system. This impedes proliferation of the GPS's.
With gradual revelation of the problem caused by the deviations between the global positioning system coordinates and the old positioning system coordinates as described above, the Ministry of Land, Infrastructure and Transport has made a detailed survey throughout the country in order to correct the deviations, and announced a new coordinate system as survey result 2000 (Geodetic Coordinates 2000). Subsequently, utilization of this new positioning system coordinates has been legislated, and the Ministry of Land, Infrastructure and Transport is making efforts to popularize of the new positioning system coordinate. However, there are few manufactures which manufacture paper maps and GIS (Geographic Information System) which support the new positioning system, and a transition to it will make very slow progress. This is because deviations between the new and old coordinate systems are not uniformly translated throughout the country, and because introduction of the latitude/longitude of the new coordinates into conventional maps for representation on the map results in distortions due to different amounts of corrections depending on regions, it is very hard to remake maps, and a failure in conversion would not cause difficult situations for ordinary private use. On the contrary, if the new positioning system and old positioning system co-exist in the market, the same values of the longitude and latitude indicate different positions separated by approximately 500 meters, so that confusion will be introduced unless a clear indication is made as to which coordinate system is employed. This can cause a more serious problem. Also, since the deviations are not simply translated between the new and old positioning systems, deviations are produced between the immense amount of existing statistic data arranged by the regional mesh codes based on the old positioning system and data based on the new positioning system, resulting in the absence of continuity in statistics, thus giving rise to a serious problem as well. Therefore, this is a situation in which difficulties will be encountered in forcedly advancing the transition. The administration has stipulated in a public survey operation rules that maps which are to be surveyed after April 2002 should be surveyed in the new coordinate system. Since privately published maps are illustrated on the basis of maps created by the Administration, it should be necessarily accepted that the old positioning system can no longer be continued as before.
Also, when viewed from the standpoint of international cultural exchange, continuing to use the old positioning system which deviates from the international standard will be a problem in aircraft and the like, so that it is thought that the transition will gradually advance in the future.
However, as the transition gradually advances, the new and old coordinates will co-exist for a longer time, possibly giving rise to a new problem. If the difference between the new and old coordinate systems was visually apparent, no mistake would be made, but since they are in the same latitude/longitude representation, a deviation between the new and old coordinates is said to be 400-500 meters even when they have the same values, so that it is anticipated that confusion can occur in a navigation system and the like if the distinction between the new and old coordinate systems is forgotten as a result of both systems using the same representation. Actually, even at the current time at which the utilization of the new positioning system has been legislated, latitude/longitude databases based on the old positioning system are still extensively sold without recognition of the need to distinguish between them.
Except for coordinates that are used in professional applications, on paper maps such as road maps, sightseeing maps and the like, familiar to general persons, coordinates are represented by letters such as A, B, C, . . . , and 1, 2, 3, . . . which are vertically and horizontally written in the margin. However, these coordinates are applied only to particular maps, leading to the inconvenience of requirements for indexes on a map-by-map basis. Moreover, general position representing methods use addresses and landmark objects, rather than the coordinates. However, these position representing methods, which are not in coordinate structure, are redundant, lack regularity, and local information, so that they have disadvantages that they are recognized only with local persons. Therefore, for convenience, on GIS, an indirect search approach has been employed using a telephone number, a postal code or the like. However, these supplementary methods also lack regularity, and basically support only places where people live, or registered positions, and present the problem that they are not available in mountain regions, on the sea, and the like.
In such a situation, the GIS is rapidly becoming increasingly popular because its importance has been recognized after the Great Hanshin Awaji Earthquake in Japan. However, the GIS, which has been devolved as a result of the need to prevent disasters, cannot support disasters in real time and fails to exert sufficient functions even though it can be used for previous predictions and post verifications. This is because the current GIS cannot directly receive positional information from in habitants and does not have a method for efficiently communicating acquired information to in habitants.
While communications of disaster information are mainly made through speeches, by telephones and the like, communicating disaster information by generally recognized addresses and landmark objects cannot be done rapidly except by a person in charge who is familiar with a region. Thus, the information by generally used addresses and landmark objects implies a problem in that, though no problem would arise in the same district, mutual positional relationships between positions are difficult to understand for those not familiar with the region in a district having a different name, even in an adjacent district, and can be only supported by those familiar with the region. Also, since the information by generally used addresses and landmark objects is not suited for entry into a computer, a long time is taken for the entry, and entry tends to be inaccurate. Then, when a support should be made by a prefecture or by the country, i.e., an area beyond an autonomous community as is the case with the Great Hanshin Earthquake, most of those who are in charge are not familiar with the region and as a result they are too busy trying to identify the location instead of attending to essential rescue activities, which gives rise to a serious problem in the crisis management.
One problem of current car navigation systems is that one cannot easily and correctly enter a destination. As a current method of searching for a destination, the destination may be looked for on a map on the screen, or searched for by a method which relies on an address, a postal code, a telephone number, the name of facilities, or the like. However, while the method of looking for the destination on the screen works well in an urban area which includes a readily identifiable landmarks, the entry is difficult it there is no landmark in an suburban area or in a mountain region, or along a coast line, or the like. On the other hand, the address and postal code search method permits only a rough identification on a district basis, and the telephone number search and facility name search method, though capable of a pinpoint search, cannot be utilized unless they have been registered, and has the disadvantage of a low hit rate. Also, with the telephone number search method, a telephone number is likely to be changed. In addition, these methods can basically support only regions where people live, but in many cases they cannot search for a suburban sightseeing spot and the like. For example, garbage is illegally dumped in a mountain region, on a river-terrace, along a coast line, or the like. Further, current car navigation systems have the disadvantage that they cannot successfully inform their own positions. For example, in the event of a rendezvous or trouble, the car navigation system can pinpoint its own position on the screen, but cannot clearly describe its own position to the partner through a portable telephone or the like.
Recently, portable telephones having a built-in GPS (Global Positioning System) have been available on the market, which permit an entry into an era in which walker ITS (Intelligent Transport Systems) is available. However, the current systems have problems. This is because, though it is impossible to expect functions such as those provided by a car navigation system to portable telephones in the screen size and storage capacity, an attempt is made to employ approaches similar to those used to the car navigation system. Specifically, the walker ITS cannot store map information therein and therefore must capture the map information by downloading, but a map screen has the disadvantage that it requires a large amount of information and provides a poor map in spite of the long download time and a high fee required, so that the user cannot recognize the region represented by the map even if the user views it on the map screen unless there is a prominent landmark therein.
Recently, according to announcements from the Police Agency, there are 8,800,000 urgent reports to the police, and the number will be higher if urgent reports to the fire department are added. It is said that 50% or more of these reports are thought to originate from portable telephones, and the percentage will be further increased in the future. With a portable telephone, its position cannot be identified through a number search, as can be done with a fixed telephone, so that the person making the report is relied on to explain the position, but this person experiences difficulties in correctly explaining the position in a short time. For this reason, many calls are disconnected before the position can be identified, resulting in a problem that emergency services cannot ready the position on time. As an action taken therefor, it is said that the Police Agency is investigating the introduction of a system which forcedly monitors the telephone number of a telephone in order to call back thereto when the police determines that there is urgency, even if the telephone is not configured to advise its telephone number, in which case the police cannot call back to that number. However, the problem cannot be sufficiently solved by the system which identifies the position, where urgent action needed by a call back method.
As described above, the current navigation system is based on a map screen, and the walker ITS which displays rough information on the small screen of a portable telephone is not a system which can be utilized by the aged, visually impaired, or those who have difficulty reading maps. Also, in Japan, if portable navigation systems can be utilized by foreign tourists, this will attract foreign tourists, but currently, there are no maps which are displayed using the Roman alphabet. Supposing that the Roman alphabet is used, Roman alphabet to be displayed would require a number of letters three or four times larger than Chinese letters, so that it is thought to be difficult to create practical maps for portable screens. As such, the development of navigation systems for foreigners is difficult with the current approach based on the map.
When one sees an old travel photograph, he knows when the photograph was taken by a date inscribed at a corner of the photograph, but he often cannot remember where the photograph was taken. There are many travel-related programs and gourmet-related programs in recent television programs, but even if a viewer wants to go to the spot, only the rough place name and a simplified diagram are displayed which are difficult even for local persons to recognize, so that eventually, the spot is not found in many cases. Also, while positional information is an important element in news programs as well, place names such as Mt. Osutaka into which a Nihon Air Line airplane crashed into, and Kamikuissiki village were repeatedly broadcast for consecutive days, but nationwide viewers could only gotten a rough impression that the location was around Mt. Fuji. In this way, although positional information is very important in many television programs, it has been so far handled in a rough manner, so that information wanted by viewers cannot be successfully communicated to them.
Conventionally, for representing a position, different methods have been employed, depending on particular objects and applications, based on address, place name, landmark object, latitude/longitude, 19-coordinate system, map and the like, without unification, and this prevents the development of GIS. Stating by way of example, positional information spoken in different languages is spoken through an interpreter which is a computer, and is alienated not only due to the inconvenience through the interpreter, but also due to the ill fitness of the interpreter for an interpretation of more highly frequently used words of positions such as addresses and landmark objects, though this interpreter is good at interpretation between the latitude/longitude and 19 coordinates. For solving this, there is a need for a common language in which conversations can be made without the interpreter.
This common language for identifying positions are coordinates which are readily understood by human beings, and can continuously represent the entire country. To make use of the accumulated immense resources of the GIS, it is essential to rely on latitude/longitude. In the GIS, there are many areas which are arranged in the 19-coordinate system, but this coordinate system represents local coordinates, and lacks the flexibility for representing the entire country as one system, but the relationship with the longitude/latitude can be processed by a computer. Basically, therefore, this resource can be utilized by converting latitude/longitude into a coordinate system which is readily understood by people.
However, it is necessary to meet many conditions such as the decimal number system, integer notation, and the like in order to create readily understandable coordinates. A code system which satisfies such conditions is disclosed (see JP-A-2000-181345).